The theme and aim of this worktheses is to project and design the construction of a commercial building. The object of the half axis dimensions 22.10 x 28.52 m, is situated in a suburb of the city of Rijeka, in the town Viškovo. The static analysis of the structures was carried out with the programming package Autodesk Robot Structural Analysis of 2014 on 3D spatial rod model. For comparison and verification of the the results, further analysis eas made by using expressions and a tables to calculate the size of the ground floor pillars of the ground of the main frame and purlins. The input data of the calculation were obtained through the activity analysis carried out in accordance with Eurocode 1 norm and its National additions. The calculation of the ports was conducted in accordance with Eurocode 3 norm. The activity analysis was carried out in regard to the effects of wind, snow, earthquake and in the usage load. It is important to note that it was the earthquake activity which was above all taken into account due to the floor joists composite construction that is located on the height of 4,75 m measured from the floor. However, the calculation demonstrated that the combination of earthquake activities is not applicable to load-bearing elements of the construction, except for the facade bracings. All elements of the construction were calculated in regard to the applicable combination of groups of elements in which they are located, in the way to meet the requirements of stability and mechanical resistance of the ultimate limit state and the serviceability limit state. The practical part of the thesis was done in the laboratory for load-bearing structures. Ultrasound examination is performed, the joint testing of welds. The interrogation was carried out a flat probe ultrasound brands Phasor XS.